<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        .box{
            width: 200px;
            height: 200px;
            background-color: red;
            float:right;
        }
        .container{
             width: 500px;
             height: 500px;
             background-color: green;
        }
        .con1{
            width: 500px;
            height: 30px;
            background-color: yellow;
        }
        ul{
            list-style:none;
        }
        ul li{
            float:left;
            margin-left:30px;
            background-color: #666;
            color: white;
        }
    </style>
</head>
<body>
    <div class="box"></div>
    <div class="container"></div>

    <div class="con1">
        <ul>
            <li>导航1</li>
            <li>导航2</li>
            <li>导航3</li>
        </ul>
    </div>
</body>
</html>